Display device

ABSTRACT

A display device includes a first substrate, a second substrate, a plurality of pixel units, a driving unit, a common electrode, and a column insulation structure. The pixel units are formed at a display area of the first substrate. The driving unit is formed at a non-display area of the first substrate. The common electrode is formed on an inner surface of the second substrate. The connecting layer is electronically connected between two conductive layers of the driving unit. The column insulation structure overlaps the connecting layer and is formed between the first and the second substrates.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application is a continuation of U.S. patent application Ser. No.13/804,980, filed Mar.. 14, 2013, which claims priority to Taiwan PatentApplication No. 101133610, filed on Sep. 14, 2012. The contents of theseprior applications are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display device, and in particular toa display device with one or more than one column insulation structuredisposed in a non-display area thereof.

2. Description of the Related Art

A liquid-crystal display panel mainly includes a color filter substrate,a thin-film transistor (TFT) array substrate, and liquid-crystal layersandwiched between the two substrates. The TFT array substrate controlsthe light transmittance characteristics of liquid-crystal material foundwithin the two substrates by adjusting an electric field to produce animage.

Generally, the liquid-crystal panel includes a display area in thecentral area of the panel, an edge area surrounding the display area,and a sealing area in the outer periphery of the panel. Located at thecenter of the panel, the display area serves as an area for displayingan image, and elements not used for displaying the image, such as tracelines, and testing members, are disposed in the surrounding edge area.The sealing area in the outer periphery completely surrounds the displaypanel, and a sealing agent is applied thereto to combine the TFT arraysubstrate and the color filter substrate.

In the edge area of the liquid-crystal panel, the output signal issupplied by conductive traces, and the conductive traces are connectedto one another through a connecting layer. In one example, the outputsignal is switched between a high-voltage level (such as 15V) and alow-voltage level (such as −10V). On the other hand, the voltage that isapplied to the common electrode on the color filter substrate maintainsa constant voltage (such as 5V) or is switched between a high-voltagelevel (such as 3.53V) and a low-voltage level (such as −1.13V). Thevoltage difference (electric field) between the connecting layer and thecommon electrode may cause corrosion of the connecting layer, and theliquid-crystal panel tends to deteriorate accordingly.

BRIEF SUMMARY OF THE INVENTION

In order to address the drawbacks of the prior art, the applicationprovides a display panel in which the electric field generated by thevoltage difference between the connecting layer and the common electrodecan be shielded.

In one exemplary embodiment, the display device includes a display panelincluding a first substrate, a second substrate, a plurality of pixelunits, a driving unit, and column insulation structure. The firstsubstrate has a display area and a non-display area outside of thedisplay area. The pixel units are formed at the display area of thefirst substrate and configured to receive an output signal. The drivingunit is formed at the non-display area of the first substrate andincludes first and second conductive layers, and first and secondinsulation layers and a connecting layer, wherein the first and secondconductive layers, and the first and second insulation layers arearranged alternately, and the connecting layers electrically connect thefirst conductive layer to the second conductive layer via thethrough-hole formed at the first and second insulation layers. Thecolumn insulation structure corresponds to the connecting layers and isformed between the first substrate and the second substrate.

In one embodiment, a width of the surface of the column insulationstructure facing the connecting layer in a horizontal direction isgreater than or equal to half of a width of the connecting layer in thehorizontal direction, and the width of the surface of the columninsulation structure facing the connecting layer in a vertical directionis greater than or equal to half of a width of the connecting layer inthe vertical direction. Additionally, a width of the column insulationstructure in the horizontal direction is greater than or equal to awidth of the through-hole in the horizontal direction.

In one embodiment, the display device further includes a liquid-crystalmaterial disposed in the display area, wherein the column insulationstructure has a dielectric coefficient which is smaller than the highestdielectric coefficient of the liquid-crystal material. The connectinglayer is formed of a material selected from ITO (Indium Tin Oxide), IZO(Indium Zinc Oxide), Al, Cu, and Mo.

In one embodiment, the display device further includes a commonelectrode formed on the inner surface of the second substrate, whereinthe voltage that is applied to the common electrode is different fromthe voltage that is applied to the connecting layer, and wherein thecolumn insulation structure is formed on the common electrode.

In one embodiment, the driving unit further includes at least onesupporting structure facing the column insulation structure andextruding in a direction toward the column insulation structure, whereinthe driving unit includes two supporting structures, and the connectinglayer is disposed between the two supporting structures. The twosupporting structures are made of an electrical conductor material, orare electrical insulators.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading thesubsequent detailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 shows a schematic view of a first substrate of a display devicein accordance with one of the embodiments of the present disclosure;

FIG. 2 shows a cross-sectional view of the display device in accordancewith one of the embodiments of the present disclosure; and

FIG. 3 shows a top view of partial elements of the display device inaccordance with one of the embodiments of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

Several exemplary embodiments of the application are described withreference to FIGS. 1 through 3, which generally relate to the generationof a secret key. It is to be understood that the following disclosureprovides various different embodiments as examples for implementingdifferent features of the application. This description is made for thepurpose of illustrating the general principles of the invention andshould not be taken in a limiting sense.

Referring to FIG. 1, the display panel of the display device 1 inaccordance with one of the embodiments includes a first substrate 10.The first substrate 10 has a display area AA, and a non-display area EAoutside of the display area AA. Liquid-crystal material 11, a pluralityof pixel units 13, a plurality of thin-film transistors 15, a pluralityof scanning lines 17 and a plurality of data lines 19 are formed at thedisplay area AA of the first substrate 10, and two driving units 20 and30 are formed at the non-display area EA of the first substrate 10. Atleast one of the two driving units 20 and 30 includes an interconnectioncircuit 40, and the interconnection circuit 40 is disposed at thenon-display area EA of the first substrate 10. In the embodiment, thedriving unit 20 is a scanning line driving circuit, and the driving unit30 is a data line driving circuit, wherein the scanning line drivingcircuit 20 and the data line driving circuit 30 are respectivelyconnected to the scanning lines 17 and the data lines 19 through theinterconnection circuits 40.

Specifically, the scanning line driving circuit 20 is connected to thescanning lines 17 through the interconnection circuit 40 and applies anoutput signal to the thin-film transistors 15 through the scanning lines17 so as to control the on/off state of the thin-film transistors 15.The data line driving circuit 30 is connected to at least one printedcircuit board 33 by a flexible circuit board 31 for receiving controlsignals from the printed circuit board 33 and further converting thecontrol signals to output signals. The output signals are transmitted toeach of the thin-film transistors 15 through the data lines 19 and theinterconnection circuit 40 so as to supply a driving voltage to thepixel units 13 to control the liquid-crystal materials 11.

Referring to FIG. 2, the interconnection circuit 40 includes a firstconductive layer 21, a first insulation layer 22, a second conductivelayer 23, a second insulation layer 24, a plurality of connecting layers25 and a plurality of supporting structures 26 (only one connectinglayer and two supporting structures are depicted in FIG. 2 forsimplification). The first conductive layer 21 is formed on the firstsubstrate 10 and configured to supply an output signal to the pixelunits 13 (FIG. 1). The first insulation layer 22 is formed on the firstconductive layer 21 and the first substrate 10. The second conductivelayer 23 is formed on the first insulation layer 22. The secondinsulation layer 24 is formed on the second conductive layer 23.

Note that the first conductive layer 21 is exposed to the outside viathe through-hole 27 of the first insulation layer 22, and the secondconductive layer 23 is exposed to the outside via the through-hole 27 ofthe second insulation layer 24, wherein the connecting layers 25 areelectrically connected between the first conductive layer 21 and thesecond conductive layer 23 by passing through the through-holes 27. Theconnecting layers 25 are formed of a material selected from ITO, IZO,Al, Cu, and Mo. The supporting structures 26 are located at two oppositesides of the connecting layers 25, wherein the supporting structures 26may be formed of an electrically conductive material or an electricallyinsulating material.

As shown in FIG. 2, the display device 1 further includes a secondsubstrate 50 and a plurality of column insulation structures 60 (onlyone column insulation structure is depicted in FIG. 2 forsimplification). The second substrate 50 faces the first substrate 10,and the inner surface of the second substrate 50 includes a commonelectrode 51 disposed thereon, wherein a voltage that is applied to thecommon electrode 51 is different from a voltage that is applied to theconnecting layer 25. Corresponding to the connecting layer 25, thecolumn insulation structures 60 are formed between the first and secondsubstrates 10 and 50. Specifically, the column insulation structures 60are formed on the common electrode 51 of the second substrate 50relative to the connecting layer 25 of the interconnection circuit 40,and the connecting layer 25 is disposed between the two supportingstructures 26, wherein the two supporting structures 26 respectivelyface the column insulation structures 60 and extrude in a directiontoward the column insulation structures 60. Therefore, the spacer formedbetween the column insulation structures 60 and the two supportingstructure 26 is smaller than the spacer formed between the columninsulation structures 60 and the connecting layer 25. Due to thedifference in the thickness of the interconnection circuit 40, thefailure of the connecting layer 25 can be avoided while the displaydevice 1 is compressed.

Note that in order to achieve the objective of shielding the electricfield, the thickness T of the column insulation structures 60 in avertical direction (thickness direction of the display device 1) maypreferably range from 0.5 um to 7 um; however, the thickness of thecolumn insulation structures 60 may be modified according to demand. Inaddition, a better shielding effect for the liquid-crystal material 11(FIG. 1) can be provided by selecting the dielectric coefficient of thecolumn insulation structures 60. For example, to prevent theliquid-crystal material 11 from electromagnetic interference, the columninsulation structure 60 should have a dielectric coefficient which issmaller than the highest dielectric coefficient of the liquid-crystalmaterial 11. In one unlimited embodiment, the column insulationstructure 60 has a dielectric coefficient ranging from 0.5 to 7.

It should be understood that although the column insulation structures60 are formed on the common electrode 51 of the second substrate 50, itshould not be limited thereto. The objective for shielding the electricfield can be achieved, if the column insulation structures 60 arepositioned between the common electrode 51 of the second substrate 50and the connecting layer 25. In the other embodiment, the columninsulation structures are formed on the connecting layer for shieldingthe electric field.

Referring to FIG. 3 which shows a top view of the display device 1showing in FIG. 2, wherein only the first conductive layer 21, thesecond conductive layer 23, the connecting layer 25, the supportingstructures 26, and the column insulation structures 60 are shown in FIG.3 for simplification. In one unlimited embodiment, to sufficientlyshield the electric field, a width W₁ of one of the column insulationstructures 60 in a horizontal direction (X direction) is greater than orequal to a width W₂ of the corresponding through-hole in the horizontaldirection, and the width W₁ of the surface of the column insulationstructure 60 facing the connecting layer 25 in the horizontal directionis greater than or equal to half of a width W₃ of the connecting layer25 in the horizontal direction. On the other hand, a width L₁ of thesurface of the column insulation structure 60 facing the connectinglayer 25 in the vertical direction (Y direction) is greater than orequal to half of a width L₂ of the connecting layer 25 in the verticaldirection.

By the arrangement that some column insulation structure is disposedbetween the first and second substrates of the display panel, theelectric field generated by the voltage difference between theconnecting layer and the common electrode can be shielded so as toprotect the connecting layer from failure due the electric field.

While the invention has been described by way of example and in terms ofpreferred embodiment, it is to be understood that the invention is notlimited thereto. On the contrary, it is intended to cover variousmodifications and similar arrangements (as would be apparent to thoseskilled in the art). Therefore, the scope of the appended claims shouldbe accorded the broadest interpretation so as to encompass all suchmodifications and similar arrangements.

What is claimed is:
 1. A display, comprising: a first substrate, havinga display area and a non-display area outside of the display area; asecond substrate facing the first substrate; a common electrode formedon an inner surface of the second substrate; a plurality of pixel unitsformed at the display area of the first substrate; a driving unit formedat the non-display area of the first substrate and comprising: a firstconductive layer formed at the non-display area of the first substrate;a first insulation layer formed on the first conductive layer; a secondconductive layer formed on the first insulation layer; a secondinsulation layer formed on the second conductive layer; and a connectinglayer formed on the second insulation layer, wherein both of the firstinsulation layer and the second insulation layer have a through-hole,respectively, and the connecting layer is electrically connected betweenthe first conductive layer and the second conductive layer by passingthrough the through-holes; and a column insulation structure overlappingthe connecting layers and formed between the first substrate and thesecond substrate, wherein the column insulation structure is spacedapart from the connecting layer by a gap, wherein the column insulationstructure is formed on the common electrode, and a voltage applied tothe common electrode is different from a voltage applied to theconnecting layer.
 2. The display as claimed in claim 1, wherein thecolumn insulation structure is located above the connecting layer. 3.The display as claimed in claim 1, wherein the column insulationstructure is formed on the common electrode.
 4. The display as claimedin claim 1, wherein a width of a surface of the column insulationstructure that faces the connecting layer in a horizontal direction isgreater than or equal to half of a width of the connecting layer in thehorizontal direction.
 5. The display as claimed in claim 1, wherein awidth of the column insulation structure in a horizontal direction isgreater than or equal to a width of the through-holes in the horizontaldirection.
 6. The display as claimed in claim 1, wherein a thickness ofthe column insulation structure in a vertical direction ranges from 0.5um to 7 um.
 7. The display as claimed in claim 1, further comprising aliquid-crystal material disposed between the first substrate and thesecond substrate, wherein the column insulation structure has adielectric coefficient which is smaller than the highest dielectriccoefficient of the liquid-crystal material.
 8. The display as claimed inclaim 1, wherein the connecting layer is formed of a material selectedfrom ITO, IZO, Al, Cu, and Mo.
 9. The display as claimed in claim 1,wherein the driving unit further comprises a supporting structure facingthe column insulation structure and extruding in a direction toward thecolumn insulation structure.
 10. The display as claimed in claim 9,wherein the driving unit comprises two supporting structures, and theconnecting layer is disposed between the two supporting structures. 11.The display as claimed in claim 10, wherein the column insulationstructure is in directly contact with the two supporting structures, anda portion of the gap is located between the two supporting structures.12. The display as claimed in claim 9, wherein the supporting structureis electrical conductor or electrical insulator.